Evidence of Evolution and Related Concepts

This set of flashcards covers key vocabulary related to evolution, including evidence of evolutionary processes, types of structures, and concepts related to phylogenetics.

Evolution

The process by which different kinds of living organisms develop and diversify from earlier forms.

Homologous structures

Anatomical features in different species that have a similar origin but may serve different functions.

Analogous structures

Features in different species that serve similar functions but do not share a common ancestral origin.

Vestigial structures

Body parts that have lost their original function through evolution.

Fossil record

The history of life as documented by fossils, which provide evidence of past organisms.

Transitional fossils

Fossils that show intermediate states between an ancestral form and that of its descendants.

Adaptive radiation

The process by which organisms diversify rapidly into a multitude of forms to adapt to various environments.

Phylogenetic tree

A diagram that represents evolutionary relationships among various biological species.

Speciation

The formation of new and distinct species in the course of evolution.

Common ancestor

A species from which two or more species have evolved.

Molecular biology

The study of biological activity at the molecular level, including the interactions between various systems of a cell.

Embryological similarities

Similarities in the development stages of embryos from different species, indicating a common ancestry.

DNA sequences

The order of nucleotides in a DNA molecule, which can be compared to determine relatedness between organisms.

Skeletal structures

The arrangement of bones in an organism, used to compare relatedness among species.

Phenotypic adaptation

The change in an organism's observable traits due to environmental pressures.

Biogeography

The study of the distribution of species and ecosystems in geographic space and through geological time.

Eohippus

An early horse ancestor from the Eocene epoch, approximately 55 million years ago.

Ichthyostega

A genus of extinct vertebrates that is considered an early ancestor of amphibians.

Pakicetus

One of the earliest known ancestors of modern whales, showing both terrestrial and aquatic adaptations.

Rodhocetus

An extinct genus of early whales from the Eocene period, partially adapted to life in water.

Durodon

A genus of ancient cetaceans that evolved later in the timeline of whale evolution.

Vestigial organs examples

Wisdom teeth, appendix, and human coccyx are all examples of vestigial structures.

Adaptive radiation examples

Darwin’s finches and the evolution of mammals from early reptiles.

Common descent

The principle that all living organisms share a common ancestor.

Calcium mineralization

The process through which calcium replaces organic material, aiding in fossil formation.

Fossilization process

The process in which organisms become buried in sediment and preserved over time.

Molecular homologies

Similarities in DNA or protein sequences between different species that suggest common ancestry.

Gill arches in embryos

Embryonic structures that appear in the early development of all vertebrates, indicating a common ancestry.

Homologous vs. Analogous

Homologous structures arise from a common ancestor; analogous structures evolve independently.

Pelvic girdle in snakes

A vestigial structure that reflects ancestral characteristics in modern snakes.

Coccyx

The vestigial tailbone in humans, a remnant of a tail from ancestral species.

Phylogenetic relationships

Connections between species reflected by evolutionary history and common ancestry.

Taxonomy

The science of classification of living organisms based on shared characteristics.

Natural selection

The process by which individuals with favorable traits are more likely to reproduce.

Convergent evolution

The independent evolution of similar traits in species of different lineages.

Divergent evolution

The accumulation of differences between closely related species, leading to speciation.

Fossil evidence of Lystrosaurus

Fossils that provide insights into early terrestrial vertebrate evolution.

Common genetic code

The universal set of rules by which information is encoded in the genetic material of organisms.

Speciation rate

The rate at which new species are formed through evolutionary processes.

Extinction

The end of an organism or a group of organisms, often related to environmental changes.

Human evolutionary lineage

The path of human evolution, tracing back to shared ancestors with other primates.

Biological classification levels

Hierarchy of biological organization from domain to species.

Phylum Chordata

The phylum that includes all vertebrate animals and some invertebrates.

Common traits in mammals

Characteristics shared by all mammals, such as mammary glands and hair.

Genetic drift

The change in the frequency of a gene variant due to random sampling.

Endemic species

Species that are native to and found only within a limited area.